In highly integrated semiconductors in recent years, a low dielectric constant films is used as an interlayer insulation film in order to solve the signal delay problem in a device and to produce a higher speed, power-saving device. There are many kinds of low dielectric constant films, including organic series and inorganic series. Now, the most common one is SiOC film in which carbon has been added to a silica film. As semiconductor devices are further miniaturized in the future, it becomes impossible to obtain sufficient low dielectric constant characteristics even in SiOC film. Therefore, it is expected to use a SiOC film made to be porous, as an interlayer insulation film.
SiOC film, however, has a problem that Si—C bond and Si—H bond in the film are severed after the film formation to generate silanol (Si—OH), resulting in increase of relative dielectric constant of the film. In order to solve such problem, there is publicly known a method in which a silane coupling agent, such as HMDS (hexamethyldisilazane), as a modifier of the film is made to act on SiOC film to chemically silylate silanol and lower relative dielectric constant of the film. Furthermore, in recent years, there has also been reported a method of using TMS-Cl (trimethylchlorosilane), TMSDMA (trimethylsilyldimethylamine), etc, in place of HMDS (Patent Publication 1). In any method, however, relative dielectric constant of the film to be obtained has not yet been satisfied.
Therefore, there has been a demand for a compound capable of modifying low dielectric constant films, such as SiOC film, to chemically silylate silanol and lower it to a satisfactory relative dielectric constant of the film.    Patent Publication 1: Japanese Patent Application Publication 2006-179913